/*
 * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
 * under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright
 * ownership. Camunda licenses this file to you under the Apache License,
 * Version 2.0; you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.camunda.bpm.model.bpmn.validation;

import java.util.Collection;

import org.camunda.bpm.model.bpmn.instance.Process;
import org.camunda.bpm.model.bpmn.instance.StartEvent;
import org.camunda.bpm.model.xml.validation.ModelElementValidator;
import org.camunda.bpm.model.xml.validation.ValidationResultCollector;

/**
 * @author Daniel Meyer
 *
 */
public class ProcessStartEventValidator implements ModelElementValidator<Process> {

  @Override
  public Class<Process> getElementType() {
    return Process.class;
  }

  @Override
  public void validate(Process process, ValidationResultCollector validationResultCollector) {
    Collection<StartEvent> startEvents = process.getChildElementsByType(StartEvent.class);
    int startEventCount = startEvents.size();

    if(startEventCount != 1) {
      validationResultCollector.addError(10, String.format("Process does not have exactly one start event. Got %d.", startEventCount));
    }
  }

}
